armfield MULTI-PUMP TEST RIG
C3 issue 8
The Armfield Multi-Pump Test Rig has been designed to demonstrate the principle operating characteristics characteristics of different types of pumps. Examples of dynamic pressure (rotodynamic) and a positive displacement type pump are included allowing the differences in performance to be compared. Pumps are used to convert mechanical energy into fluid energy and allow liquids to be moved from from one place to another. Student engineers must understand fully the types of pumps available and their different different characteristics. characteristics. Measurements Measurements of head, head, flow, speed and torque allow the performance of each pump to be determined and and compared. compared.
20
15
DEMONSTRATION CAPABILITIES ➤
Measuring manometric manometric head across a pump using Bourdon gauges connected to the inlet and discharge
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Measuring flowrate through a pump using a volumetric tank or knife edge weir
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Determining the power absorbed by a pump from measurements of torque and speed of dynamometer dynamometer motor motor
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Determining the performance of a pump at constant speed by producing a set of characteristic characteristic curves, namely, manometric head, power absorbed by the pump and pump efficiency, all all plotted against against flow
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Determining the effect of speed on the performance of a pump by producing a set of characteristic characteristic curves curves
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Understanding Understanding the difference between dynamic pressure type pumps and positive displacement displacement type type pumps Investigating Investigating the effect of suction losses on a centrifugal pump .
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7
30 14
EFFICIENCY
6
25
5
) M ( 4 D A E 3 H
12 U
) 20 M ( D15 A E H
INCREASING PUMP SPEED
10 8 6
10
HEAD
2
4
5
2
1
P M P E F F I C I E N C Y ( H )
0 0
0 0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0.1
0.2
1.0
0.3
0.4
0.5
0.6
FLOW (L/S)
FLOW (L/S) Comparison of pump head - flow characteristics for a centrifugal pump at three different different speeds
Pump head and pump efficiency plotted against flow for a turbine (regenerative) pump at constant speed
70
INCREASING PUMP SPEED 1.0
60
0.8
50
) M ( 0.6 D A E0.4 H
) M ( 40 D A E30 H 20
0.2
10 0
0
0.5
1.0
1.5
FLOW (L/S)
2.0
0 0
0.1
0.2
0.3
0.4
FLOW (L/S) Pump head plotted against flow for an axial pump at constant speed
Comparison of pump head-flow characteristics for a gear pump at different speeds
DESCRIPTION
A self-contained unit unit with four different different water pumps and and measuring instrumentation instrumentation incorporated within within a mobile, floor-standing floor-standing framework. framework. The four pumps supplied are: centrifugal pump, turbine (regenerative) pump, axial flow pump, gear pump. A dc shunt wound wound dynamometer dynamometer motor with variable speed control control can be easily connected connected to any of the pumps pumps by a toothed drive belt. The pumps pumps and motor are enclosed enclosed within a cage which incorporates a micro switch in the access door which disconnects the electrical supply to the motor when changing the drive belt. The motor speed is controlled via a dc thyristor speed controller. A non-contacting speed sensor is positioned positioned on the the drive shaft of the the motor and the the corresponding corresponding speed is indicated indicated on an analogue tachometer. Torque is measured on an accurate knife edge beam balance with dual scales for high and low ranges. The balance is directly calibrated in Newton metres. Pressure at the discharge of each pump is indicated on an appropriate Bourdon gauge. gauge. Suction at the inlet of each pump is indicated on a common Bourdon vacuum gauge. The above instrumentation is mounted on an instrument panel and shelf for convenience of measurement and control. control. Pump discharge can be measured using either the calibrated volumetric tank or a set of knife edged weirs. Water is returned to an integral sump tank via a dump valve in the bottom of the volumetric tank. The sump tank and volumetric tank are manufactured from glass reinforced plastic. The valves and pipework are suitably arranged for quick and safe selection of any one of the test pumps.
TECHNICAL DETAILS
Dynamo Dynamomet meter er motor motor:: dc shunt shunt woun wound d 0.56kW 0.56kW
Pressure gauges:
Bourdon tubes calibrated in m H 20
Torque Torque measurem measurement ent 0 to 1 Nm range: and 0.5 to 3.5 Nm
Vacuum gauge: calibrated
Bourdon tu tube 0 to -10m H 20
Speed co controller:
Thyristor ty type incorporating closed closed loop armature
Flow rate measurement:
Centr entrif ifug uga al Pum Pump p:
Pede edestal stal typ type wit with h shrouded impeller. impeller. Pressure gauge range 0 to 10m H 20
Volumetric tank calibrated 0 to 6 litres for low flows and 0 to 40 litres for higher flows. Water level measurement by by remote sight gauge gauge or
Motor speed:
Axial Flow Pump: Pump:
Gear Pump:
Turbine Pump: impeller
1450rpm
Housed in a clear clear acrylic casing. Pressure gauge range 0 to 2m H 20 Positive displacement pump fitted with non adjustable relief relief valve. Pressure gauge range 0 to 75m H 20 Straight bladed in annular casing. Pressure gauge range 0 to 40m H 20
'V' notch and rectan rectangula gularr notch weirs. weirs. Water level measurement by by 150mm hook and point Vernier gauge, resolution 0.1mm Tachometer:
Electronic, no contact type Range 0 to 3000rpm
ORDERING SPECIFICATION
A self-contained mobile mobile unit consisting consisting of four different pumps and measurement instrumentation. Supplied Supplied with a dc dynamometer, sump tank, volumetric tank and interconnecting pipework and valves. Instrumentation includes torque measurement, tachometer with with analogue read-out. Bourdon gauges gauges to measure delivery pressures. Bourdon vacuum gauge to measure suction suction at pump inlet. GRP volumetric tank with low and high flow ranges. Knife edge weirs for flow measurement. Basic unit includes includes the following four four pumps: centrifugal centrifugal pump, turbine turbine pump, axial flow pump, pump, gear pump. Speed range range 0 to 3000rpm.
RECOMMENDED INSTRUMENTS
Stop clock SERVICES REQUIRED
C3-11C3-11-A: A: 220V/2 220V/240V 40V/1p /1ph/5 h/50Hz 0Hz C3-11C3-11-B: B: 120V/1 120V/1ph/ ph/60H 60Hz z OVERALL DIMENSIONS
Height:
1.62m
Width:
3.00m
Depth:
0.80m
SHIPPING SPECIFICATIONS
C3-11 Volume:
3.9m 3
Gross weight:
500kg
Torque measurement 0 to 1Nm and 0.5 to 3.5Nm dual range. Variable Variable speed control by dc thyristor controller. controller.
Armfield Limited Bridge House West Street Ringwood Hampshire England BH24 1DY Tel: +44 (0)1425 478781 Fax: +44 (0)1425 470916 E mail:
[email protected] [email protected] URL: http://www.armfield.co.uk http://www.armfield.co.uk USA Office: Armfield Inc. 510 N. Main Street Denison Iowa 51442 Tel: (712) 263-5885 Fax: (712) 263-8884 E mail:
[email protected]
Specifications Specifications may change without notice 5k/1200/BS.
